#!/bin/bash
#If no argument is specified, ask for it and exit
# if [[ -z "$@" ]];
# then
#     echo "An argument is needed to run this script";
#     exit
# else
#     arg="$@"
#     #Basic check to make sure argument number is valid. If not, display error and exit
#     if [[ $(($(echo $arg | grep -o "\s" | wc --chars) / 2 )) -ne 2 ]];
#     then
#         echo "Invalid Parameters. You need to specify parameters in the format \"width height refreshRate\""
#         echo "For example setResolution \"1920 1080 60\""
#         exit
#     fi
    
    #Save stuff in variables and then use xrandr with those variables
    arg="1920 1080 60"
    modename="1920x1080_60.00"
    display=$(xrandr | grep -Po '.+(?=\sconnected)')
    if [[ "$(xrandr|grep $modename)" = "" ]];
    then
        xrandr --newmode $modename $(gtf $(echo $arg) | grep -oP '(?<="\s\s).+') &&
        xrandr --addmode $display $modename     
    fi
    xrandr --output $display --mode $modename

    #If no error occurred, display success message
    if [[ $? -eq 0 ]];
    then
        echo "Display changed successfully to $arg"
    fi

<<COMMENT
#Manual steps with explanation ahead by @debloper
# First we need to get the modeline string for xrandr
# Luckily, the tool "gtf" will help you calculate it.
# All you have to do is to pass the resolution & the-
# refresh-rate as the command parameters:
gtf 1920 1080 60

# In this case, the horizontal resolution is 1920px the
# vertical resolution is 1080px & refresh-rate is 60Hz.
# IMPORTANT: BE SURE THE MONITOR SUPPORTS THE RESOLUTION

# Typically, it outputs a line starting with "Modeline"
# e.g. "1920x1080_60.00"  172.80  1920 2040 2248 2576  1080 1081 1084 1118  -HSync +Vsync
# Copy this entire string (except for the starting "Modeline")

# Now, use "xrandr" to make the system recognize a new
# display mode. Pass the copied string as the parameter
# to the --newmode option:
xrandr --newmode "1920x1080_60.00"  172.80  1920 2040 2248 2576  1080 1081 1084 1118  -HSync +Vsync

# Well, the string within the quotes is the nick/alias
# of the display mode - you can as well pass something
# as "MyAwesomeHDResolution". But, careful! :-|

# Then all you have to do is to add the new mode to the
# display you want to apply, like this:
xrandr --addmode VGA1 "1920x1080_60.00"

# VGA1 is the display name, it might differ for you.
# Run "xrandr" without any parameters to be sure.
# The last parameter is the mode-alias/name which
# you've set in the previous command (--newmode)

# It should add the new mode to the display & apply it.
# Usually unlikely, but if it doesn't apply automatically
# then force it with this command:
xrandr --output VGA1 --mode "1920x1080_60.00"

# That's it... Enjoy the new awesome high-res display!
COMMENT
